In two of the closest asteroids on Earth, astrophysicists found signs that their past was not a tour of the solar system. While in Ryugu the Japanese probe Hayabusa2 spotted glowing stones on the surface, NASA’s OSIRIS-REx found on Bennu rocks that look like Vesta, one of the largest objects in the asteroid belt between Mars and Jupiter.
Ryugu is a type C asteroid, made of carbon and water, one of the most common in the outer belt of the asteroid belt. Studying images sent by Hayabusa2, scientists from the Japan Aerospace Exploration Agency (JAXA) identified stones twice as shiny as the material from which Ryugu is made.
They would be aluminum silicate, the most common material in type S asteroids. “One rock may be a coincidence, but not many of them,” Space Eri Tatsumi, an astrophysicist at the University of La Laguna and lead author of the study published in the journal Nature, told the website Astronomy. Since type S bodies are inside the belt, Ryugu probably originated there.